The Federal Aviation Administration sent a letter to FedEx in March 2008 “advising that FedEx was operating aircraft with ULDs in violation of published FAA standards and without approved maintenance and operation procedures,” according to the lawsuit.

The government identified 14 ULDs FedEx used on 124 flights between March 2008 and April 2008, according to the suit.

The lawsuit also claims FedEx did not have standards in place to determine time limitations for use of the devices, nor for their overhaul, replacement, periodic inspection and routine check.